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There are many factors known to drive species turnover although the mechanisms by which these operate are less clear. Based on comprehensive datasets we used zeta diversity and multi-site generalized dissimilarity modelling to investigate the pattern and determinants of species turnover for Lepidoptera herbivores. We found that the average number of shared herbivore species declined sharply with an increasing number of plots, with complete changes in caterpillar species composition observed even at fine spatial scales. Plant community characteristics rather than abiotic factors were found to play key roles in driving caterpillar compositional turnover, although these effects varied with increasing plots due to the varying contributions of rare and common species to compositional turnover. Our study reveals details of the impact of phylogeny- and trait- mediated processes of trees on herbivore compositional turnover, which has implications for forest management and conservation and potential avenues for maintenance of heterogeneity in herbivore communities.

Alzheimer’s disease (AD) is the most common cause of dementia in older adults. Neuropathological and imaging studies have demonstrated a progressive stereotyped accumulation of protein aggregates, but the underlying molecular and cellular mechanisms driving AD progression and vulnerable cell populations affected by disease remain coarsely understood. The current study harnesses the BRAIN Initiative Cell Census Network experimental practices, combining quantitative neuropathology with single cell genomics and spatial transcriptomics, to understand the impact of disease progression on middle temporal gyrus cell types. We used quantitative neuropathology to place 84 cases spanning the spectrum of AD pathology along a continuous disease pseudoprogression score. We used multiomic technologies to profile single nuclei from each donor, mapping their identity to a common cell type reference with unprecedented resolution. Temporal analysis of cell-type proportions indicated an early reduction of Somatostatin-expressing neuronal subtypes and a late decrease of supragranular intratelencephalic-projecting excitatory and Parvalbumin-expressing neurons, with increases in disease-associated microglial and astrocytic states. We found complex gene expression differences, ranging from global to cell type-specific effects. These effects showed different temporal patterns indicating diverse cellular perturbations as a function of disease progression. A subset of donors showed a particularly severe cellular and molecular phenotype, which correlated with steeper cognitive decline. We have created a freely available public resource to explore these data and to accelerate progress in AD research at SEA-AD.org.

Alzheimer’s disease (AD) is the most common cause of dementia in older adults. Neuropathological and imaging studies have demonstrated a progressive and stereotyped accumulation of protein aggregates, but the underlying molecular and cellular mechanisms driving AD progression and vulnerable cell populations affected by disease remain coarsely understood. The current study harnesses single cell and spatial genomics tools and knowledge from the BRAIN Initiative Cell Census Network to understand the impact of disease progression on middle temporal gyrus cell types. We used image-based quantitative neuropathology to place 84 donors spanning the spectrum of AD pathology along a continuous disease pseudoprogression score and multiomic technologies to profile single nuclei from each donor, mapping their transcriptomes, epigenomes, and spatial coordinates to a common cell type reference with unprecedented resolution. Temporal analysis of cell-type proportions indicated an early reduction of Somatostatin-expressing neuronal subtypes and a late decrease of supragranular intratelencephalic-projecting excitatory and Parvalbumin-expressing neurons, with increases in disease-associated microglial and astrocytic states. We found complex gene expression differences, ranging from global to cell type-specific effects. These effects showed different temporal patterns indicating diverse cellular perturbations as a function of disease progression. A subset of donors showed a particularly severe cellular and molecular phenotype, which correlated with steeper cognitive decline. We have created a freely available public resource to explore these data and to accelerate progress in AD research atSEA-AD.org.

The pyrolysis of PDA offered a mild synthesis method to optimize the conductivity and interface force of the CNT–Fe3O4 conductive network. The electromagnetic absorption bandwidth of RTFs can reach 8.32 GHz.

Human-induced biodiversity loss negatively affects ecosystem function, but the interactive effects of biodiversity change across trophic levels remain insufficiently understood. We sampled arboreal spiders and lepidopteran larvae across seasons in 2 years in a subtropical tree diversity experiment, and then disentangled the links between tree diversity and arthropod predator diversity by deconstructing the pathways among multiple components of diversity (taxonomic, phylogenetic and functional) with structural equation models. We found that herbivores were major mediators of plant species richness effects on abundance, species richness, functional and phylogenetic diversity of predators, while phylogenetic, functional and structural diversity of trees were also important mediators of this process. However, the strength and direction differed between functional, structural and phylogenetic diversity effects, indicating different underlying mechanisms for predator community assembly. Abundance and multiple diversity components of predators were consistently affected by tree functional diversity, indicating that the variation in structure and environment caused by plant functional composition might play key roles in predator community assembly. Our study highlights the importance of an integrated approach based on multiple biodiversity components in understanding the consequences of biodiversity loss in multitrophic communities.

Global change exposes forest ecosystems to many risks including novel climatic conditions, increased frequency of climatic extremes and sudden emergence and spread of pests and pathogens. At the same time, forest landscape restoration has regained global attention as an integral strategy for climate change mitigation. Owing to unpredictable future risks and the need for new forests that provide multiple ecosystem services, mixed-species forests have been advocated for this purpose. However, the successful establishment of mixed forests requires intrinsic knowledge of biodiversity's role for forest ecosystem functioning. In this respect, a better understanding of tree-tree interactions and how they contribute to observed positive tree species richness effects on key ecosystem functions is critical. Here, we review the current knowledge of the underlying mechanisms of tree-tree interactions and argue that positive net biodiversity effects at the community scale may emerge from the dominance of positive over negative interactions at the local neighbourhood scale. In a second step, we demonstrate how tree-tree interactions and the immediate tree neighbourhood's role can be systematically assessed in a tree diversity experiment. The expected results will improve predictions about the effects of tree interactions on ecosystem functioning based on general principles. We argue that this knowledge is urgently required to guide the design of tree species mixtures for the successful establishment of newly planted forests.

Herbivorous insects acquire microorganisms from host plants or soil, but it remains unclear how the diversity and functional composition of host plants contribute to structuring herbivore microbiomes. Within a controlled tree diversity setting, we used DNA metabarcoding of 16S rRNA to assess the contribution of Lepidoptera species and their local environment (particularly, tree diversity, host tree species, and leaf traits) to the composition of associated bacterial communities. In total, we obtained 7,909 bacterial OTUs from 634 caterpillar individuals comprising 146 species. Tree diversity was found to drive the diversity of caterpillar‐associated bacteria both directly and indirectly via effects on caterpillar communities, and tree diversity was a stronger predictor of bacterial diversity than diversity of caterpillars. Leaf toughness and dry matter content were important traits of the host plant determining bacterial species composition, while leaf calcium and potassium concentration influenced bacterial richness. Our study reveals previously unknown linkages between trees and their characteristics, herbivore insects, and their associated microbes, which contributes to developing a more nuanced understanding of functional dependencies between herbivores and their environment, and has implications for the consequences of plant diversity loss for trophic interactions., In this study, we hypothesized that the community composition of herbivore‐associated microbes is driven by specific aspects of their surroundings (particularly, leaf traits, host tree species, and diversity thereof) and by the composition and diversity of the host herbivore species. We found that tree diversity and leaf traits drive caterpillar‐associated microbes in a controlled setting. It revealed the linkages between tree (leaves), herbivores, and associated microbes, which contributes to the development of a more comprehensive understanding of relationships and functional dependencies between herbivores and their environment, and of the consequences of plant diversity loss for trophic interactions.

From regional to global scales, anthropogenic environmental change is causing biodiversity loss and reducing ecosystem functionality. Previous studies have investigated the relationship between plant diversity and functional insect communities in temperate and also in tropical grasslands and forests. However, few studies have explored these dynamics in subtropical forests. Here, cavity-nesting Hymenoptera and associated parasitoids were collected across a controlled tree diversity experiment in subtropical China to test how predatory wasps, bees and parasitoids respond to tree species richness. Abundance and species richness of predatory wasps and parasitoids were positively correlated with tree species richness, while bee abundance and bee species richness were unrelated to tree species richness. Our results indicate that tree species richness increases the abundance and species richness of important communities such as predators and parasitoids. Moreover, the results highlight the importance of subtropical forests in maintaining abundance and species richness of key functional insect groups.

Global biodiversity decline and its cascading effects through trophic interactions pose a severe threat to human society. Establishing the impacts of biodiversity decline requires a more thorough understanding of multi-trophic interactions and, more specifically, the effects that loss of diversity in primary producers has on multi-trophic community assembly. Within a synthetic conceptual framework for multi-trophic beta-diversity, we tested a series of hypotheses on neutral and niche-based bottom-up processes in assembling herbivore and carnivore communities in a subtropical forest using linear models, hieratical variance partitioning based on linear mixed-effects models (LMMs) and simulation. We found that the observed taxonomic, phylogenetic and functional beta-diversity of both herbivorous caterpillars and carnivorous spiders were significantly and positively related to tree dissimilarity. Linear models and variance partitioning for LMMs jointly suggested that as a result of bottom-up effects, producer dissimilarities were predominant in structuring consumer dissimilarity, the strength of which highly depended on the trophic dependencies on producers, the diversity facet examined, and data quality. Importantly, linear models for standardized beta-diversities against producer dissimilarities implied a transition between niche-based processes such as environmental filtering and competitive exclusion, which supports the role of bottom-up effect in determining consumer community assembly. These findings enrich our mechanistic understanding of the 'Diversity Begets Diversity' hypothesis and the complexity of higher-trophic community assembly, which is fundamental for sustainable biodiversity conservation and ecosystem management.全球范围内生物多样性下降正对全球生态系统功能构成威胁。而特定类群的生物多样性下降又会通过营养级关系(例如，bottom-up effect上行效应和top-down effect下行效应)对不同营养级类群的生物多样性和整个生态系统产生复杂影响。在此背景下，揭示不同营养级之间生物多样性变化的关联机制对于理解多营养级组成的群落构建和生物多样性的维持机制至关重要。在多营养级群落构建机制的研究中，最为经典的“Diversity begets diversity”理论常常用于解释不同营养级alpha多样性的关联机制研究，而对于营养级之间多维度beta多样性的关联机制研究相对较少。 本研究依托中国亚热带生物多样性与生态系统功能 (BEF-China，江西德兴) 野外实验样地，对植物、植食性无脊椎动物(鳞翅目幼虫)和捕食性无脊椎动物(蜘蛛)的物种组成、功能特征数据进行了系统调查，并构建不同类群物种的种间系统发育关系。根据生态位理论和中性理论的预测，本研究分别在beta多样性观测值空间格局、beta多样性观测值变异解释和beta多样性标准值空间格局三个维度提出假设，系统评估了亚热带森林中植物组成(代表生态位过程中的上行效应)和空间距离(代表中性扩散过程)对这两个营养级群落构建的相对重要性。 研究表明，植食性和捕食性无脊椎动物的物种、谱系和功能beta多样性均与植物beta多样性存在显著正相关关系。基于线性混合模型的方差分解结果表明，植物组成的变化通过上行效应决定了植食性和捕食性无脊椎动物的群落组成结构，并且该影响同时受到营养级关系强度、多样性维度和数据质量(0-1数据/基于多度的数据)的影响。此外，基于零模型分析的beta多样性标准值空间格局也证实了生态位过程在植食性和捕食性无脊椎动物群落构建过程中的重要性。 综上所述，这些研究结果证实了植物beta多样性通过上行效应对其高营养级类群beta多样性的影响机制，进一步拓展了我们对亚热带森林中多营养级群落构建及生物多样性维持机制的理解。.

The early diversification of angiosperms is thought to have been a rapid process, which may complicate phylogenetic analyses of early angiosperm relationships. Plastid and nuclear phylogenomic studies have raised several conflicting hypotheses regarding overall angiosperm phylogeny, but mitochondrial genomes have been largely ignored as a relevant source of information. Here we sequenced mitochondrial genomes from 18 angiosperms to fill taxon-sampling gaps in Austrobaileyales, magnoliids, Chloranthales, Ceratophyllales, and major lineages of eudicots and monocots. We assembled a data matrix of 38 mitochondrial genes from 107 taxa to assess how well mitochondrial genomic data address current uncertainties in angiosperm relationships. Although we recovered conflicting phylogenies based on different data sets and analytical methods, we also observed congruence regarding deep relationships of several major angiosperm lineages: Chloranthales were always inferred to be the sister group of Ceratophyllales, Austrobaileyales to mesangiosperms, and the unplaced Dilleniales was consistently resolved as the sister to superasterids. Substitutional saturation, GC compositional heterogeneity, and codon-usage bias are possible reasons for the noise/conflict that may impact phylogenetic reconstruction; and angiosperm mitochondrial genes may not be substantially affected by these factors. The third codon positions of the mitochondrial genes appear to contain more parsimony-informative sites than the first and second codon positions, and therefore produced better resolved phylogenetic relationships with generally strong support. The relationships among these major lineages remain incompletely resolved, perhaps as a result of the rapidity of early radiations. Nevertheless, data from mitochondrial genomes provide additional evidence and alternative hypotheses for exploring the early evolution and diversification of the angiosperms. Jiangsu Key Laboratory for the Research and Utilization of Plant Resources (Institute of Botany, Jiangsu Province) [KSPKLB201835]; Jiangsu Key Laboratory for the Research and Utilization of Plant Resources (Chinese Academy of Sciences) [KSPKLB201835]; Shenzhen Key Laboratory of Southern Subtropical Plant Diversity [SLPD-2018-3]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [31470314, 31471200, 31470448]; Public Welfare Forestry Industry Project of State Forestry Administration, China [201504322]; Special Research Fund of Ghent UniversityGhent University [BOFPDO2018001701]; Strategic Priority Research Program of Chinese Academy of SciencesChinese Academy of Sciences [XDA13020603]; Shenzhen Fairy Lake Botanical Garden Science Foundation [FLSF-2019-02]; Ghent UniversityGhent University; FWOFWO; Flemish Government-department EWI info:eu-repo/semantics/publishedVersion

Declining plant diversity alters ecological networks, such as plant-herbivore interactions. However, our knowledge of the potential mechanisms underlying effects of plant species loss on plant-herbivore network structure is still limited. We used DNA barcoding to identify herbivore-host plant associations along declining levels of tree diversity in a large-scale, subtropical biodiversity experiment. We tested for effects of tree species richness, host functional and phylogenetic diversity, and host functional (leaf trait) and phylogenetic composition on species, phylogenetic and network composition of herbivore communities. We found that phylogenetic host composition and related palatability/defence traits but not tree species richness significantly affected herbivore communities and interaction network complexity at both the species and community levels. Our study indicates that evolutionary dependencies and functional traits of host plants determine the composition of higher trophic levels and corresponding interaction networks in species-rich ecosystems. Our findings highlight that characteristics of the species lost have effects on ecosystem structure and functioning across trophic levels that cannot be predicted from mere reductions in species richness.

Plant diversity loss can alter higher trophic -level communities via non -random species interactions, which in turn may cascade to affect key ecosystem func-tions. These non -random linkages might be best captured by patterns of phyloge-netic diversity, which take into account co -evolutionary dependencies. However,lack of adequate phylogenetic data of higher trophic levels hampers our mecha-nistic understanding of biodiversity relationships in species-rich ecosystems.2. We used DNA barcoding to generate data on the phylogenetic diversity of lepi-dopteran caterpillars in a large- scale forest biodiversity experiment in subtropicalChina. We analysed how different metrics of lepidopteran phylogenetic diversity(Faith's PD, MPD, MNTD) and taxonomic diversity were influenced by multiple components of tree diversity (taxonomic, functional, phylogenetic).3. Our data from six sampling periods represent 7,204 mitochondrial cytochrome c oxidase subunit I (COI) sequences of lepidopteran larvae, clustered into 461 mo-lecular operational taxonomic units. Lepidopteran abundance, the effective num-ber of species (irrespective of the focus on rare or common species) and Faith's PD and MPD (reflecting basal evolutionary splits), but not MNTD (reflecting re-cent evolutionary splits), significantly increased with experimentally manipulated ree species richness. Lepidopteran MNTD decreased with increasing tree MNTD. Path analyses showed that tree phylogenetic and functional diversity explained part, but not all of the effects of tree species richness on lepidopteran diversity. Importantly, tree diversity effects on lepidopteran diversity were to a large extent indirect, operating via changes in lepidopteran abundance. 4. Synthesis. Our study shows that evolutionary dependencies determine the response of herbivore communities to changes in host plant diversity. Incorporating a wider range of diversity metrics both at the level of producers and consumers can thus help to develop a more comprehensive understanding of the functional consequences of biodiversity change across trophic levels. Moreover, the dependence of trophic linkages on herbivore abundances underlines the need to address the consequences of current declines in insect abundances for ecosystem structure and functioning. peerReviewed

Four new cytochalasans, arbuschalasins A-D (1-4), along with thirteen known analogues (5-17), were isolated from the solid rice medium of endophytic fungus Xylaria arbuscula. Arbuschalasins A-B feature a rare 5/6/6/6 fused ring system while arbuschalasin D was characterized as the first example of natural cytochalasans that possesses a 5/5/11 fused scaffold. The structures of 1-4 were assigned by spectroscopic data, with their absolute structures being determined by electronic circular dichroism (ECD) calculations. All of the isolates were evaluated against the human colorectal adenocarcinoma cell lines (HCT15). Compounds 6 and 7 showed significant inhibitory effects (IC

Lead halide perovskites have emerged as promising optoelectronic materials due to their excellent efficiencies in photovoltaic and light-emitting applications. CsPbBr3 is a kind of all-inorganic perovskite that exhibits higher stability. Here, we report the synthesis of hexagonal and circular all-inorganic CsPbBr3 perovskite nanoplates by changing the reaction temperature. As time goes on, the different reaction temperatures play an important role in determining the shape and size. We use first-principles to explicate the formation of hexagonal nanoplates. Meanwhile, a model is built and the calculation of the properties is conducted. In brief, a method to directly and conveniently synthesize all-inorganic CsPbBr3 is proposed.

Nine species of the genus Coenodomus (including one unnamed species) are recognized from China. Among them, four species are described as new to science: C. anacanthos sp. nov., C. pachycaulosus sp. nov., C. puniceus sp. nov. and C. stigma. sp. nov. Two species, C. fumosalis (Hampson, 1903) and C. rotundinidus Hampson, 1891 are reported in China for the first time. All adults and their genital structures are illustrated. A key to the Chinese species and an updated checklist of the genus are provided.

Ten species of the genus Lista are recognized from China. Among them, five species are described as new to science, namely, Lista angustusa sp. n., Lista gilvasa sp. n., Lista longifundamena sp. n., Lista menghaiensis sp. n., and Lista sichuanensis sp. n. Diagnoses are provided for the genus and five previously described species, Lista haraldusalis (Walker, 1859), Lista insulsalis (Lederer, 1863), Lista ficki (Christoph, 1881), Lista plinthochroa (West, 1931), and Lista variegata (Moore, 1888), that occur in China. Two species, Lista plinthochroa and Lista variegata, are reported from China for the first time. All adults and their genital structures are illustrated. A key to the Chinese species is provided.

ObjectiveTo investigate the cellular mechanisms of action of tanshinone IIA on the fatty liver disease induced by a high-fat diet in an animal model of non-alcoholic fatty liver disease (NAFLD).MethodsAdult male Sprague Dawley rats were randomized into one of three groups: regular rat diet (CON group) for 4 months; high-fat diet (HFD group) for 4 months; HFD for 2 months followed by tanshinone IIA treatment plus HFD (TAN group) for a further 2 months. A range of physical and biochemical markers of lipid accumulation and fatty liver disease were measured and compared between the groups.ResultsTanshinone IIA treatment significantly reduced fat accumulation in the liver and plasma lipid levels that had been increased by HFD. The toll-like receptor (TLR4)/nuclear factor kappa B (NF-κB) signalling pathway was silenced by tanshinone IIA treatment. Tumour necrosis factor-α and interleukin-6 were reduced by tanshinone IIA. Hepatocyte apoptosis was inhibited by tanshinone IIA. Tanshinone IIA upregulated peroxisome proliferator-activated receptor gamma (PPAR-γ), which resulted in an improvement in the oxidative status.ConclusionTanshinone IIA ameliorates NAFLD by targeting PPAR-γ and TLR4, resulting in decreased plasma lipids and oxidative stress, suggesting this strategy may form the basis of novel NAFLD therapies.

Human African trypanosomiasis (HAT), also known as sleeping sickness, causes millions of deaths worldwide. HAT is primarily transmitted by the vector tsetse fly (Glossina morsitans). Early diagnosis remains a key objective for treating this disease. MicroRNAs (miRNAs) are evolutionarily conserved small non-coding RNAs that play key roles in vector-borne diseases. To date, the roles of proteins and miRNAs in HAT disease have not been thoroughly elucidated. In this study, we have re-annotated the function of protein-coding genes and identified several miRNAs based on a series of bioinformatics tools. A batch of 81.1 % of tsetse fly proteins could be determined homology in mosquito genome, suggesting their probable similar mechanisms in vector-borne diseases. A set of 11 novel salivary proteins and 14 midgut proteins were observed in the tsetse fly, which could be applied to the development of vaccine candidates for the control of HAT disease. In addition, 35 novel miRNAs were identified, among which 10 miRNAs were found to be unique in tsetse fly. Pathway analysis of these 10 miRNAs indicated that targets of miR-15a-5p were significantly enriched in the HAT-related neurotrophin signaling pathway. Besides, topological analysis of the miRNA-gene network indicated that miR-619-5p and miR-2490-3p targeted several genes that respond to trypanosome infection, including thioester-containing protein Tep1 and heat shock protein Hsp60a. In conclusion, our work helps to elucidate the function of miRNAs in tsetse fly and establishes a foundation for further investigations into the molecular regulatory mechanisms of HAT disease.

Two new genera of Epipaschiinae are described. The genus Arcanusa Wang, Chen & Wu, gen. n. is established for Ar. apexiarcanusa Wang, Chen & Wu, sp. n. and Ar. sinuosa (Moore, 1888), comb. n., described in Scopocera Moore, 1888 (junior synonym of Stericta Lederer, 1863). The female genitalia of Ar. sinuosa (Moore, 1888), comb. n. are described for the first time. Androconia Wang, Chen & Wu, gen. n. is erected, including two new species, An. rallusa Wang, Chen & Wu, sp. n. and An. morulusa Wang, Chen & Wu, sp. n. Illustrations of all adults and their genitalia, and a key to the two new genera are provided.

Modulation recognition is an important issue in cognitive radio research area, however, high recognition precision is usually achieved by relative large number of training data and more various features of digital signal, which call for much more resource. In this paper, a novel modulation recognition approach is proposed, 4th order cyclic cumulants vectors of digital signal is applied for modulation recognition, which are constructed as features to train support vector machine classifiers for further recognition. The experimental result shows the proposed approach can get comparative high precision for ASK, BPSK and PSK signal recognition in additive white Gaussian noise channel while using relative small number of training samples and small in dimension, which reduce cost remarkably.

Traditional decoupling control strategy of doubly-fed induction generator (DFIG) wind turbine makes little contribution to system inertia and do not participate in the system frequency control, the synchronization of large-scale wind power requires wind turbine have the ability to participate in the regulation of power system frequency. This paper adds a frequency control segment to traditional DFIG wind turbine and considers the doubly-fed wind turbine operating on the state of the super-synchronous speed, by analysis the effect of inertia and proportional control strategies, a fuzzy control strategy which combines the advantages of the former two control strategies is proposed, simulation results show that this control strategy can more effectively improve the system frequency response.

In this paper, the conventional method to acquire Thevenin equivalent parameters is described. The method is based on features of power systems and utilizes the base-case system information. Considering the impact of loads on Thevenin equivalent potential and impedance, this paper makes improvements and brings it closer to the actual situation. The necessary condition about limit power transmission is derived, and the impedance modulus margin can be used to determine voltage stability of power system. Finally, the results of IEEE-14 bus system calculations show effectiveness of the method.

Aqueous CdTe quantum dots(QDs) with different colors were synthesized. Fluorescence spectroscopy analysis showed that synthesized CdTe QDs possessed narrow size distribution. TEM image indicated that the average size of CdTe QDs was 4nm. Fluorescent fibers were prepared by electrospinning mixed solution of CdTe QDs and CA. SEM and TEM photographs showed that the diameters of fibers were 300-700nm, QDs were well dispersed in CA fibers. Fluorescence micrograph showed the fluorescence color and brightness of QDs were not significantly changed after compounding QDs into fibers. The addition of QDs resulted in improvement of crystallinity of the composite fibers by XRD observation.

This paper demonstrates techniques for modeling fluid-structure interactions with moving mesh in COMSOL Multiphysics. It illustrates how fluid flow can deform surrounding structures and how to solve for the flow in a continuously deforming geometry using the arbitrary Lagrangian-Eulerian (ALE) technique. The ALE method handles the dynamics of the deforming geometry and the moving boundaries with a moving grid.

This paper shows how to model two immiscible fluids, tracking the fluid-fluid interface with the level set method. An oil bubble rises through water and merges with oil already residing at the top of the container. The Level Set application mode finds the fluid interface by tracing the isolines of the level set function.

Protein-protein interactions play key roles in the development of organisms and the response to biotic and abiotic stresses. Several wet-lab methods have been developed to study this challenging area,including yeast two-hybrid system, tandem affinity purification, Co-immunoprecipitation, GST Pull-down, bimolecular fluorescence complementation, fluorescence resonance energy transfer and surface plasmon resonance analysis. In this review, we discuss theoretical principles and relative advantages and disvantages of these techniques,with an emphasis on recent advances to compensate for limitations.

Spinning reserve (SR) is an important resource which can safeguard power systems without involuntary load shedding. Increasing the SR requirement can reduce the probability and severity of loss of load. However providing SR has a cost. So the SR requirement needs to be assigned appropriately. A multi-step method is proposed to estimate SR in a large traditional power system. The expected energy not supplied (EENS) is modeled as a piecewise linear function of system spinning reserve. Then the nonlinear and combinatorial natures are extracted from the model and the computation efficiency is greatly improved. A modified multi-step method is proposed to estimate SR in microgrids. EENS is classified by outage orders. EENS caused by first order outage events is calculated directly using unit commitment variables. EENS caused by high order outage events is modeled as piecewise linear function and captured step by step. Then the computation efficiency is greatly improved. DOCTOR OF PHILOSOPHY (EEE)

Based on the saturated-unsaturated seepage theory and shearing strength theory, the coupling analysis of the seepage field and the stress field was carried out by the numerical simulation using the two-phase flow configuration in FLAC. The safety factor of the slope was calculated by the shear strength reduction method. The influence of the duration and intensity of the rainfall and soil's saturated permeability coefficient to the slope stability was investigated. The results show that as the duration of the rainfall increases, the safety factor of the slope decreases; while the intensity of the rainfall keeps smaller than the saturated permeability coefficient, there is a positive correlation between the saturated permeability coefficient and the safety factor.

In 2006-2008, a field experiment was conducted at the Tongzhou Experimental Base for Water-Saving Irrigation Research, Chinese Academy of Sciences, Beijing, aimed to study the effects of sprinkler irrigation amount on the growth, grain yield, water consumption, and water use efficiency of winter wheat. Different treatments were installed, with the irrigation amounts expressed by the multiples of the evaporation (E) from a standard 20-cm diameter pan placed above winter wheat canopy. The grain yield was the highest in treatment 0.75 E in 2006-2007 and in treatment 0.625 E in 2007-2008. In treatments with irrigation amount less than 0.25 E, winter wheat growth was subjected to water stress, and the yield loss was larger than 25%. The water consumption of winter wheat in the two growth seasons was in the range of 219-486 mm, and increased with increasing irrigation amount. The relationships between the grain yield and the water consumption and water use efficiency could be described by quadratic function. Sprinkler irrigation with an amount of 0.50-0.75 E was recommended for the winter wheat growth after its turning green stage in Beijing area.

Yttrium fluoride compounds with different crystal phases and morphologies, including rice-like orthorhombic-phase YF3:Yb3+/Er3+, and octahedral and quasi-spherical tetragonal-phase LiYF4:Yb3+/Er3+ microcrystals have been synthesized under hydrothermal conditions by tuning the pH value of the mother solution. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and photoluminescence spectra were used to characterize the samples. It is found that the pH value in the initial reaction solution has significant effects on selective adsorption of the organic additive EDTA on different crystal facets controlling the final sizes and geometries of the particles. Meanwhile the pH value in conjunction with hydrothermal reaction time affects the solubility constants and thermodynamic stability of reactants and products, further triggering the phase transformation from orthorhombic-phase YF3 to tetragonal-phase LiYF4 and controlling the nucleation and anisotropic growth of fluoride microcrystals. The possible formation mechanisms for products with various architectures have been presented. The multicolor upconversion (UC) luminescence was successfully realized in a series of Yb3+/Er3+ codoped fluoride microcrystals by excitation in the NIR region, and the UC emissions were investigated as a function of the pH value. Results show that the UC luminescence of microparticles sharply increases with pH elevation. The enhancement was attributed to Li+ interstitials in the channels of LiYF4, which is consistent with the growth mechanism of LiYF4 microcrystals, while the possibility of doping Li+ in the cation vacancies of LiYF4 cell cannot be fully excluded because of the presence of the cation defects. The study further demonstrates that the pH tuning approach can be used as an efficient tool to control the crystal phase, size and the improvement of luminescence emission for fluoride microcrystals.